The present invention relates to a semiconductor device and, for example, to a semiconductor device including an analog-to-digital conversion circuit.
In a semiconductor device, in order to perform processing about an analog signal in a digital circuit, the analog-to-digital conversion circuit which converts an analogue value of the analog signal into a digital value is used. One type of the analog-to-digital conversion circuit is a successive comparison type analog-to-digital conversion circuit. In the successive comparison type analog-to-digital conversion circuit, there is a case where a redundant comparison operation is performed to correct misjudgment caused by various noises and settling error.
Accordingly, Non-patent Document 1 discloses an example of the analog-to-digital conversion circuit which performs a redundant comparison operation. As to the analog-to-digital conversion circuit of Non-patent Document 1, an input signal is given as a difference signal, and a comparator and two wirings by which the difference signal is delivered to the comparator are provided. In this regard, in the analog-to-digital conversion circuit of Non-patent Document 1, some capacitors have capacitance which corresponds to the same weight etc., and a redundant compare treatment is performed using one of the electrostatic capacitor of this same capacitance variation. Then, by performing this redundant comparison processing, the analog-to-digital conversion circuit of N-patent Document 1 corrects an incorrect judgment.